CVE-2020-1763
libreswan: DoS attack via malicious IKEv1 informational exchange message
Severity
ImportantRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · May 11, 2020
Updated · November 22, 2025
Description
An out-of-bounds buffer read flaw was found in the pluto daemon of libreswan. An unauthenticated attacker could use this flaw to crash libreswan by sending specially-crafted IKEv1 Informational Exchange packets. The daemon respawns after the crash.
Statement
This flaw does not affect the version of libreswan shipped with Red Hat Enterprise Linux 6 and 7 because they did not ship the vulnerable code. (The offending commit fa004e7d4b83fbeaa8d0f6d8430a96aed97a97b9 and others was introduced in libreswan-3.27)
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update as soon as possible.
CVSS / CWE
CVSS 3.1 · 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE-125 · Out-of-bounds Read